CXB3590 Change qustion. 2x2

Hello.
I have 4X CXB3590 CD 36V runing at 36W in 2x2 space (36W/psqf) - 194lm/W info from forum.
a friend wants to make it same from my. And I have 2 option.

Option 1:
Sell this light and make new one for me more efficiency.

4X Vero 29 C 3000k CRI90 (BXRC-30G10K0-C-7X ) Run realy low- 35W per COB - with price 104 usd
or
2X QB 288 3000K Run at 70W - but price is over 170 USD
or something more eff.

Option 2:
keep it CXB3590

Please can you give me some advice?
Sorry for my english.

Thx

use the 3590's ..they will do excellent....most of the growing has to do with your grow talent

3590's are still relevent and good

Are those CXB really >190 lm/w at that current? hard to believe from an 'old' cob. Maybe I am mistaken. If you decide to use a strip / midpower led build I think you can gain about 20% light for the same power. That's my experience going from cobs to strips.

That said I agree with @OLD MOTHER SATIVA

Notwithstanding, If I was in your position, I would be tempted to sell the cobs for the price of my own new diy 2x2 strip fixture. Since you are going to be building anyway.

10WeekFlushBro said:

Are those CXB really >190 lm/w at that current? hard to believe from an 'old' cob. Maybe I am mistaken. If you decide to use a strip / midpower led build I think you can gain about 20% light for the same power. That's my experience going from cobs to strips.

That said I agree with @OLD MOTHER SATIVA

Notwithstanding, If I was in your position, I would be tempted to sell the cobs for the price of my own new diy 2x2 strip fixture. Since you are going to be building anyway.

Click to expand...

Cxb's have a max efficiency of 174lm/w. At the current he is running he is probably quite close to that number.
He would not gain 20% efficiency going to strips

Indeed, in that case I stand corrected

I found this thread - COB efficiency Spreadsheets https://www.rollitup.org/attachments/cxb-3500k-png.3486878/

At 700ma - 207 lm/w
At 1400ma - 182 lm/w
190 lm/w is between.

What should I buy for same space build?

Again 4X CXB3590? 4 Vero 29 C is not better? (run at 35W)

Thx

few years back i builded a CXB3590 based light for a 2x2, 4COB CXB3590 on a 120w driver and a 3x3 5 COB CXB3590, 240w setup.
the light in the 3x3 got replaced in the menatime, for the 2x2 it made less sense as coverage is allready pretty good using 4 cobs in a 2x2 area.

but you need a complete new second lamp it seems.
if i would build new from scratch i would consider a board or strip build, quite some options out there, cost wise about the same as a vero build.
you will win a few cm, cause the heatsinks (if any needed) are lower profile, this can matter in a 2x2x4 (guessing the tent is not very tall).
also a option is a chilled logic puck maybe, if you like the form factor of the cobs.

Thank you for you ansver. Yes i need second light for same space 2x2.
What is better choise?
14x EBstrip Gen3 3000k 80cri - BXEB-L0590U-30G1500-C-C3 (90cri out of stock) 10W each / 140W
or 4 vero 29 C 3000K 90CRI. 37 35W ech / 140W

Tent is DIY 2x2x5. height is not problem.

If your looking for a cheap option that is also efficient, I just bought and installed 3 "B-Grade" pucks from chilled tech. They only have cosmetic damage. You can probably mount them to your existing heatsinks.

Thaks. But i need something from eu or china. I'm looking for the most effective option,

Now I have 4x CXB3599 CD 36v total 140W and I have always 1,25-1,4 GPW. I wont make some better light for this space.

Demas said:

Thank you for you ansver. Yes i need second light for same space 2x2.
What is better choise?
14x EBstrip Gen3 3000k 80cri - BXEB-L0590U-30G1500-C-C3 (90cri out of stock) 10W each / 140W
or 4 vero 29 C 3000K 90CRI. 37 35W ech / 140W

Tent is DIY 2x2x5. height is not problem.

Click to expand...

I like all options presented here, especially 90 cri but youll have to order more than 100 to get 90cri bxeb. Have you considered blux vesta strips? 2700k 90cri and 5000k channels on the same strip

Now I look only in to vesta strips datasheet. In forum find only effiency as like EBGgen2 series. Isn't the third series better?

Of course but somewhat more expensive and 90cri is not available anywhere. Vestas are nice for 2 spearate channels and so many (around 200) diodes for 10$.

I saw with my own eyes vestas 2700k 90cri outflower samsung 3000k 80cri, same amount of diodes and watts, but slightly different form factor.

Vero 29 C 2700k CRI 90 - 76.7 W Have 143lm/W
Vesta strips 2700k CRI 90 - 24.8W - 129ml/W (3x)
Price is 26 usd VS 30 usd.
Look Vero29C is 10% more effective and 15% usd cheaper like Vesta strips.
Where i make mistake?

I havent checked any numbers but you would need to add up heatsinks for all and holder for your cob for cost but id expect it to come out similar.

Also, 143 lm/w at what junction temp? 74 w thru slightly more than a square inch of cob instead of around 24w thru 24 square inch of strip is a big difference in thermal management.

Personally i prefer not to run cobs that hard. They need alot of hanging height which means lost yield (thru smaller plants) in most cases. How much light is lost to walls from hanging them higher and how much more even can you get the strips?

Also the strips come with 2 channels which is also interesting for full cycle.

you brought up some valid points Demas.
am not so deep in to cobs anymore myself as strips n boards give really a better spread etc., i compared to my old 240w cob fixture with 5 3590.
light distribution is much more even, you have quite some gaps in between the cobs.

but as i said i am not so sure about that in a 2x2 space, i would have to measure the 2x2 fixture which is at a friend and isnt replaced to date btw.
we drove the cobs there in a similar range as you do in the 2x2, pretty low.
if you have 4 cobs in a 2x2 you may have what you want in spread.

can you lend a luxmeter from somewhere, or get one for 20 bucks?
just to check the spread and see if thats what you want.

you hardly cant go wrong with any option you found or are mentioned here.

Rocket Soul - you're right. I forgot the coolers.

All same parametr. 2700k 90CRI Around 140W complet.

Vero 29C 35W from graph can hit 160lm/W - Price is 4x26usd + alpine 4x 11usd. - Complet 22400lm - 148 usd (Passive cooling)

EB GEN3 13,4W 156lm/W - 11x 8,64 usd + aluminuim plate 11x 1usd. (147,4W) - Complet 22900lm - 106 usd (Passive cooling)
- in this optio i can buy 4 pcs more and run lower. price same like Vero. eff better

Vesta strips 24,8W 129lm/W 7x 9,97usd + aluminuim plate 7x1usd (173,6 W) - Complet 22395lm - 76,8 usd (Passive cooling)
-for this option I need 24% more Watage for same lm. efficiency is worse than 3 years old CXB3590
I can buy 6 more pcs but it will never be that good like first 2 option and my old CXB3590 at 35W
This is perfect for low budget or first test growers.

I want something with best eff. at this moment it looks like 15x EB GEN3 is best option something like DIY from cobshopgrow.

It might also be a good idea to remember that you cannot make a lum to lum comparison between between 80 and 90 cri. Divide lum per watt with the luminous efficacy rating (LER) for each and compare, for 3000k 80cri its aroundd 330, for same but 90 cri around 280.

But the real gain is in plant response to increased reds and far reds.

Also for 35w per cob dont use vero 29C, they are comparatively expensive for performance, you could use luminous cxm for about 19$ with same or even higher efficiency.

could be wrong but i think he compared only 2700k 90cri to each other, so he can compare lumen to lumen?.

the luminous cxm is a good tip, there where some movement after the cxb3590.